fix 311 by adding <title>s

add an application helper file for dynamically changing title with a default
define titles for submissions and exercises
add tests for default and defined title
Fix different duplicates test
Add CodeClimate's badge to README.

[ci skip]
rna: Ditch first example.
rna: Extend example.

Forward ==, to_str, to_s.
Extract NucleicAcid baseclass.
Add RibonucleicAcid class.
rna: Extend tests. Use long classnames.
adjustments for changes that fix 311

more specific helper name
titles now have slugs, language, and user
Adding more tests for silence to Bob

The Elixir suite case doesn't current check for nil, while the Ruby test
suite demands that nil be understood as a form of silence. This adds a
test to the Elixir quite to check for nil.

It also adds a test case for a different kind of "empty" string: one
consisting solely of spaces, such as "    ".  Both of these test suites
will now check to see that is correctly interpreted as silence rather
than shouting (because "  ".upcase == "  ").
Top level navigation by language

This splits the server side rendering by language with links along the
top nav bar. Home now navigates to nitless submissions from all
languages.
Remove unused date routing code

Not squashing these commits so the code stays indexed. This is a lesser
act of code hoarding.
Create many seeds for realism
Tweak ruby:leap-year
Probably best not to show inheriting from core classes.
Note about using `.ruby-version` should you wish
Improve setup instructions for development
Update bob_test.rb

This clear the screen, regardless of its height.
Update anagram_test.rb
Merge pull request #328 from sbagdat/patch-1

Fix different duplicates test
Merge pull request #342 from Nerian/patch-1

Update bob_test.rb
Merge pull request #332 from pck/extended-rna-transcription-test-v2

Extended rna transcription test v2